It's tempting bait but I won't bite -- I note you're another signup from back in September-October '04, sort of like the cicadas who bury themselves in the ground for a few years then come out for a few short weeks in the heat and do nothing but make loud annoying noise.
However, in answer to your question, one size doesn't fit all. But I live down here and in lots of places there are no fences worth noting. A few broken strands of barbed wire, continually replaced by a rancher to keep his cattle on this side of the border, for example. Here some concrete barriers and heavy steel mesh with wire on top might do the job. It can be cut you say? Likely, but with a backup of actual patrols, regular maintenance and some sensors it should do the job.
In San Diego you may need an Israeli type wall -- double high concrete walls with wire on top. I think we can skip the mine fields.
In El Paso, some years ago they completed a long fence and illegals and crime both have decreased in the city proper. What bothers me more when I work there are the Anglo "homeless" people who panhandle at the traffic lights at the freeway access points. They all speak English. But out to the east along the river, you can drive a four wheel drive vehicle back and forth and US agents and local sheriffs have been shot and shot at. Again, a virtual wall with no one around to apprehend those who cross the border will not help. A physical barrier will at least help even the odds.
Now its past time for you to go back into hibernation.
The media attempts to divide the Republican party are increasing daily now-looks like it is working
Informative and civil response. Thank you.